Item | Information |
---|---|
CAS RN | 1307-96-6 |
Chemical Name | Cobalt(II) oxide |
Substance ID | H27-B-051/C-087B_P |
Classification year (FY) | FY2015 |
Ministry who conducted the classification | Ministry of Health, Labour and Welfare (MHLW)/Ministry of the Environment (MOE) |
New/Revised | Revised |
Classification result in other fiscal year | FY2014 FY2006 |
Download of Excel format | Excel file |
Item | Information |
---|---|
Guidance used for the classification (External link) | GHS Classification Guidance for the Japanese Government (FY2013 revised edition (Ver. 1.1)) |
UN GHS document (External link) | UN GHS document |
Definitions/Abbreviations (Excel file) | Definitions/Abbreviations |
Model Label by MHLW (External link) | MHLW Website (in Japanese Only) |
Model SDS by MHLW (External link) | MHLW Website (in Japanese Only) |
OECD/eChemPortal (External link) | eChemPortal |
Hazard class | Classification | Pictogram Signal word |
Hazard statement (code) |
Precautionary statement (code) |
Rationale for the classification | |
---|---|---|---|---|---|---|
1 | Explosives | Not applicable |
- |
- | - | There are no chemical groups associated with explosive properties present in the molecule. |
2 | Flammable gases (including chemically unstable gases) | Not applicable |
- |
- | - | Solid (GHS definition). |
3 | Aerosols | Not applicable |
- |
- | - | Not aerosol products. |
4 | Oxidizing gases | Not applicable |
- |
- | - | Solid (GHS definition). |
5 | Gases under pressure | Not applicable |
- |
- | - | Solid (GHS definition). |
6 | Flammable liquids | Not applicable |
- |
- | - | Solid (GHS definition). |
7 | Flammable solids | Not classified |
- |
- | - | It is not combustible (ICSC (2004)). |
8 | Self-reactive substances and mixtures | Not applicable |
- |
- | - | There are no chemical groups present in the molecule associated with explosive or self-reactive properties. |
9 | Pyrophoric liquids | Not applicable |
- |
- | - | Solid (GHS definition). |
10 | Pyrophoric solids | Not classified |
- |
- | - | It is not combustible (ICSC (2004)). |
11 | Self-heating substances and mixtures | Not classified |
- |
- | - | It is not combustible (ICSC (2004)). |
12 | Substances and mixtures which, in contact with water, emit flammable gases | Not classified |
- |
- | - | It is estimated that it does not react vigorously with water because water solubility was measured. Water solubility: 3.13 mg/L (GESTIS (Access on August 2015)) |
13 | Oxidizing liquids | Not applicable |
- |
- | - | Solid (GHS definition). |
14 | Oxidizing solids | Classification not possible |
- |
- | - | It is an inorganic compound containing oxygen (but not halogen), but the classification is not possible due to no data. |
15 | Organic peroxides | Not applicable |
- |
- | - | It is an inorganic compound. |
16 | Corrosive to metals | Classification not possible |
- |
- | - | Test methods applicable to solid substances are not available. |
Hazard class | Classification | Pictogram Signal word |
Hazard statement (code) |
Precautionary statement (code) |
Rationale for the classification | |
---|---|---|---|---|---|---|
1 | Acute toxicity (Oral) | Category 3 |
Danger |
H301 | P301+P310 P264 P270 P321 P330 P405 P501 |
Based on the LD50 values for rats of 159 mg/kg (ATSDR (2004)), 202 mg/kg (Environmental Risk Assessment for Chemical Substances Vol.11 (Ministry of the Environment, 2013)), this substance was classified in Category 3. |
1 | Acute toxicity (Dermal) | Classification not possible |
- |
- | - | Classification not possible due to lack of data. |
1 | Acute toxicity (Inhalation: Gases) | Not applicable |
- |
- | - | Solid (GHS definition) |
1 | Acute toxicity (Inhalation: Vapours) | Not applicable |
- |
- | - | Solid (GHS definition) |
1 | Acute toxicity (Inhalation: Dusts and mists) | Classification not possible |
- |
- | - | Classification not possible due to lack of data. |
2 | Skin corrosion/irritation | Classification not possible |
- |
- | - | Classification not possible due to lack of data. Besides, there is a description that this substance may cause mechanical irritation (Environmental Risk Assessment for Chemical Substances Vol.11 (Ministry of the Environment, 2013)). |
3 | Serious eye damage/eye irritation | Classification not possible |
- |
- | - | Classification not possible due to lack of data. Besides, there is a description that this substance may cause mechanical irritation (Environmental Risk Assessment for Chemical Substances Vol.11 (Ministry of the Environment, 2013)). |
4 | Respiratory sensitization | Category 1 |
Danger |
H334 | P304+P340 P342+P311 P261 P284 P501 |
Japan Society For Occupational Health (JSOH) classified cobalt compounds in occupational sensitizers to the airway Group 1 (Recommendation of Occupational Exposure Limits (2015)). Therefore, it was classified in Category 1. Besides, there is a description that not all substances related to sensitization are identified (Recommendation of Occupational Exposure Limits (Japan Society For Occupational Health (JSOH), 2015)). |
4 | Skin sensitization | Category 1 |
Warning |
H317 | P302+P352 P333+P313 P362+P364 P261 P272 P280 P321 P501 |
Japan Society For Occupational Health (JSOH) classified cobalt compounds in occupational skin sensitizers Group 1 (Recommendation of Occupational Exposure Limits (2015)). Therefore, it was classified in Category 1. Besides, there is a description that not all substances related to sensitization are identified (Recommendation of Occupational Exposure Limits (Japan Society For Occupational Health (JSOH), 2015)). Besides, this substance is classified as "Skin sens. 1 H317" in EU CLP classification (ECHA CL Inventory (Access on September 2015)). |
5 | Germ cell mutagenicity | Classification not possible |
- |
- | - | Classification not possible due to lack of data. |
6 | Carcinogenicity | Category 2 |
Warning |
H351 | P308+P313 P201 P202 P280 P405 P501 |
Though it is not this substance itself, there were multiple epidemiologic studies which suggested a relationship between occupational exposure to cobalt or cobalt compounds and lung cancer mortality. All of these were evaluated by IARC and the groups were concurrently exposed to nickel or arsenic, etc. or concurrently exposed to other hard-metal dusts, and the effects were not due to cobalt alone. Therefore, it was concluded that the evaluable information on carcinogenicity in humans was insufficient (IARC 52 (1991)). On the other hand, as for the experimental animals, positive results were obtained as follows: sarcoma was observed in the local injection site of rats 25-74 weeks after intramuscular injection of this substance powder (cobalt oxide) in two tests (20-30 mg/rat, single dose); benign or malignant pulmonary tumors increased at a low incidence 2 years after intratracheal injection of cobalt oxide powder suspension in saline at constant intervals to rats; and an increase in local tumors (histiocytoma, sarcoma, mesothelioma) was observed in tests with rats by subcutaneous or intraperitoneal injection of cobalt oxide powder (IARC 52 (1991)). In contrast, there was a report that it was negative in one test, in which hamsters were exposed to cobalt oxide dust by inhalation (10 mg/m3, exposed through the life), however, IARC concluded there was enough evidence for carcinogenicity of cobalt oxide in the experimental animals, and classified carcinogenicity of cobalt and cobalt compounds as a whole in "Group 2B" (IARC 52 (1991)). Other than this, ACGIH classified cobalt (elemental and inorganic compounds) as "A3" (ACGIH (7th, 2001)), Japan Society for Occupational Health (JSOH) classified cobalt and cobalt compounds as "2B" (Recommendation of Occupational Exposure Limits (2015)). From the above, this substance was classified in Category 2 for this hazard class according to the GHS classification guidance for the Japanese government. Besides, IARC evaluated the carcinogenicity of metallic cobalt particles in 2006 and classified cobalt metal with tungsten carbide in Group 2A because there is limited evidence for an increased risk of lung cancer by occupational exposure at production facilities, but classified cobalt metal without tungsten carbide in Group 2B (IARC 86 (2006)). |
7 | Reproductive toxicity | Classification not possible |
- |
- | - | Classification not possible due to lack of data. |
8 | Specific target organ toxicity - Single exposure | Category 1 (liver), Category 2 (heart) |
Danger Warning |
H370 H371 |
P308+P311 P260 P264 P270 P321 P405 P501 |
There is no human data on this substance. As for experimental animals, reported were hyperemia of the liver, structural change in hepatocytes observed by oral dose (157.3 mg/kg, corresponding to Category 1) to rats and proliferation of the heart interstitial cells, hypertrophy and degeneration of the myocardial fiber observed by oral dose (795 mg/kg, corresponding to Category 2) to rats (ATSDR (2004)) only. From the above, the heart and the liver were selected as the target organs, and it is classified in Category 1 (liver) and Category 2 (heart). |
9 | Specific target organ toxicity - Repeated exposure | Category 1 (respiratory organs, thyroid, haemal system) |
Danger |
H372 | P260 P264 P270 P314 P501 |
There is no toxicity information on humans with obvious exposure to this substance itself. Regarding the health effects of cobalt and cobalt compounds in humans, there is the following information, which is considered to be available for the hazard assessment of this substance: It is described that in workers exposed to airborne cobalt during diamond polishing, the chief complaints of symptoms in the respiratory organs such as coughs, and effects on lung function (significant decreases in the forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and maximal mid-expiratory flow rate (MMEF)) were observed as the cases of high concentration exposure (Environmental Risk Assessment for Chemical Substances Vol.11 (Ministry of the Environment, 2013), CICAD 69 (2006), ACGIH (7th, 2001)); and it is described that in workers in cobalt refineries, skin lesions (eczema, erythema), respiratory symptoms (dyspnea, wheezing, chronic bronchitis), decreased pulmonary function, anemia (decreases in red blood cell count, hemoglobin level, and hematocrit value), and effects on thyroid function (low T3 values, abnormal values in thyroid hormones) were observed (Environmental Risk Assessment for Chemical Substances Vol.11 (Ministry of the Environment, 2013), CICAD 69 (2006), ACGIH (7th, 200)). Among the symptoms listed above, the skin lesions were thought to be due to skin sensitization. It was, therefore, deemed to be findings out of the scope of the specific target organs. In experimental animals, there is a description that in a test in which hamsters were exposed to this substance by whole life inhalation, pulmonary emphysema, proliferative change in the alveolar epithelium and distal bronchus were observed at 10 mg/m3 (converted guidance value: 0.0083 mg/L/6 hr/day) (Environmental Risk Assessment for Chemical Substances Vol.11 (Ministry of the Environment, 2013), CICAD 69 (2006)). From the above, it is considered appropriate to regard the effects of repeated exposure to cobalt and cobalt compounds in humans as those by repeated exposure to this substance. Therefore, this substance was classified in Category 1 (respiratory organs, thyroid, haemal system). |
10 | Aspiration hazard | Classification not possible |
- |
- | - | Classification not possible due to lack of data. |
Hazard class | Classification | Pictogram Signal word |
Hazard statement (code) |
Precautionary statement (code) |
Rationale for the classification | |
---|---|---|---|---|---|---|
11 | Hazardous to the aquatic environment (Acute) | Classification not possible |
- |
- | - | No data available. |
11 | Hazardous to the aquatic environment (Long-term) | Classification not possible |
- |
- | - | No data available. |
12 | Hazardous to the ozone layer | Classification not possible |
- |
- | - | No data available. |
* A blank or "-" in a cell of classification denotes that the classification of the hazard class was not conducted. * Hazard_statement_and/or_Precautionary_statement will show when hovering the mouse over a code of Hazard_statement_and/or_Precautionary_statement. Hazard_statement_and/or_Precautionary_statement are also provided in the Excel file. * Classification was conducted by relevant Japanese Ministries in accordance with GHS Classification Guidance for the Japanese Government, and is intended to provide a reference for preparing GHS labelling and SDS for users. * This is a provisional English translation of classification results and is subject to revision without notice. * The responsibility for any resulting GHS labelling and SDS referenced from this site is with users. * Codes assigned to each of the hazard statements and codes for each of the precautionary statement are based on the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) in United Nations. |